双头螺柱脱扣失效原因分析及装配工艺优化  

Stripping Failure Analysis and Assembly Process Optimization of Double-End Studs

作　　者：付玄 孙惠斌[2] 刘自成 徐广庆 童浩 FU Xuan;SUN Huibin;LIU Zicheng;XU Guangqing;TONG Hao(AECC Sichuan Gas Turbine Establishment,Mianyang 621000,China;Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]中国航发四川燃气涡轮研究院,绵阳621000 [2]西北工业大学,西安710072

出　　处：《航空制造技术》2024年第3期89-95,共7页Aeronautical Manufacturing Technology

基　　金：“两机”重大专项基础研究项目(2017-VII-0010);四川省军工科研院所稳定支持专项(GJCZ-0810-20)。

摘　　要：针对目前某型航空发动机中介机匣单元体上双头螺柱松动脱扣问题,从安装强度、外加载荷、制造缺陷等方面进行全面的故障原因分析和排查,得出主要原因为自锁螺母分解力矩大于相配双头螺柱的安装力矩;其次流道高温、机体振动都将进一步加剧双头螺柱的疲劳失效,并在此基础上提出基于温差及振动组合方式的双头螺柱装配工艺方法,即首先对螺柱进行加热处理,然后在拧紧过程中对螺柱添加轴向高频振动。通过对比试验及应用验证,双头螺柱的平均脱扣失效故障率从21.6%降低至3.2%,证明上述工艺方法能有效提高双头螺柱装配质量,在不破坏螺纹牙配合质量的情况下增加双头螺柱的安装强度及稳定性,从而大幅度减小双头螺柱脱扣失效情况的出现,保证了航空发动机试验及飞行过程中的安全性和可靠性。In order to solve the problem of loosening and stripping of double-end studs on the intermediate casing of an aero-engine,the comprehensive failure analysis and troubleshooting were carried out from the aspects of installation strength,applied load and manufacturing defects.The main reason is that the decomposition torque of the self-locking nut is greater than the assembly torque of studs.Secondly,the high temperature of the cavity and the vibration of the engine will further aggravate the fatigue failure of the studs.And the assembly process of double-end studs based on the combination of temperature difference and vibration was proposed,where the stud was firstly heated,and then axial highfrequency vibration was added to the stud during the tightening process.Comparison tests and application experiments were performed.Results show that the average stripping failure rate of the double-end stud decreases from 21.6%to 3.2%,that is,the proposed assembly process can effectively improve the assembly quality of double-end studs,and increase the installation strength and stability of studs without damaging the quality of the thread teeth.The stripping failure of double-end studs is avoided effectively and the safety and reliability of aero-engine during test and flight are guaranteed.

关 键 词：航空发动机 双头螺柱 脱扣失效 温差装配 高频振动 

分 类 号：V263.2[航空宇航科学与技术—航空宇航制造工程]